Research On Sensing Technology Based On Optoelectronic Oscillator

With the development of microwave photonic technology,the sensors based on microwave photonics have attracted more and more attention by researchers.The microwave photonic sensor is a cross product of microwave photonics technology and fiber-optic sensing technology.Not only does it have the advantages of fast speed and high sensitivity of microwave photonic technology,but also it inherites the advantages from a fiber-optic sensor such as anti-electromagnetic interference,low loss and high bandwidth.It has played a very active role in the development of sensor technology and it will find applications in all kinds of life.This paper is mainly about the optical fiber sensing technology based on optoelectronic oscillator(OEO),which is based on the photoelectric oscillation technology,utilizing the phase modulator and phase-shifted fiber Bragg grating(PSFBG)to implement a microwave photon filter as the sensing element with high-precision measure of temperature and pressure parameters.This paper theoretically analyzes the basic principle of fiber-optic sensing technology,the basic principle of optoelectronic oscillators,the basic characteristics of Bragg gratings and the basic structure of PSFBGs.The mainly accomplished research work is as follows:the experimental studies on single loop and dual-loop optoelectronic oscillators.The advantages and disadvantages of the signals generated by the two structures are analyzed by comparing the generated microwave signals.A single-loop photoelectric oscillation and dual-loop photoelectric oscillation are used to realize temperature sensing measurement.It is more advantageous to adopt the double loop structure by comparing the final experiment results.With the existing experimental conditions,the sensitivity and resolution that the experiment can achieve are 1.21 GHz/? and 0.1?,respectively.This kind of experimental structure can realize the accurate measurement of temperature and ultra-fast demodulation.